KR102288101B1 - Vehicle control device - Google Patents

Abstract

A vehicle control device is mounted on a vehicle having a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force. The vehicle control device includes a processor (21). The processor 21 is configured to determine, when a predetermined condition including at least that the vehicle is decelerating is satisfied, the sum of the magnitude of the required driving force and the magnitude of the required braking force is the direction of movement of the vehicle by gravity acting on the vehicle. and correcting the required driving force and the required braking force to the increasing side, respectively, so as to be greater than or equal to the magnitude of the component of .

Description

Vehicle Control Device {VEHICLE CONTROL DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a vehicle control apparatus, and more particularly, to a vehicle control apparatus including a drive actuator for applying a driving force and a braking actuator for applying a braking force.

Japanese Patent Laid-Open No. 2011-255808 discloses a technique for suppressing slippage when a vehicle is traveling uphill by automatic driving. According to this technology, the target axle torque is calculated based on the vehicle's running resistance including the target acceleration of the vehicle and the effect of gravity according to the road gradient, and based on the target axle torque, the axle torque to be requested by the driving actuator and the braking actuator The required axle torque is determined. Then, when the rearward sliding of the vehicle is predicted while driving on an uphill road, the target axle torque is corrected to increase the braking force by the braking actuator. Further, when the vehicle slippage occurs even when the target axle torque is corrected, the proportional gain of the feedback control of the target axle torque is increased so as to minimize the slippage amount.

The above technique performs control for preventing the vehicle from sliding down on an uphill road, while also performing follow-up control when the vehicle slipping occurs. That is, the above technique does not exclude the possibility of the vehicle sliding down on an uphill road. However, in order to eliminate the discomfort felt by the occupant, it is desired to suppress the vehicle's retreat on the uphill road with high certainty. SUMMARY OF THE INVENTION The present invention provides a vehicle control device capable of suppressing retreat of a vehicle on an uphill road.

A vehicle control apparatus according to a first aspect of the present invention is mounted on a vehicle including a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force. The vehicle control device includes a processor. The processor is configured to: based on a component of a motion direction of the vehicle of a required acceleration for the vehicle and a gravity acting on the vehicle, such that an acceleration in a motion direction of the vehicle acting on the vehicle meets the required acceleration, and set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator. The processor is configured to control the driving actuator based on the requested driving force. The processor is configured to control the braking actuator based on the required braking force. The processor is configured to determine that, when a predetermined condition including at least that the vehicle is decelerating is satisfied, the sum of the magnitude of the required driving force and the magnitude of the required braking force is a component of a motion direction of the vehicle of gravity acting on the vehicle. and correcting the required driving force and the required braking force to the increasing side, respectively, so as to be greater than or equal to the magnitude.

According to the vehicle control device according to the first aspect of the present invention, the processor is configured such that, when a predetermined condition including at least that the vehicle is decelerating is satisfied, the sum of the magnitude of the required driving force and the magnitude of the required braking force is calculated as the gravity acting on the vehicle The required driving force and the required braking force are corrected to the increasing side, respectively, so as to be greater than or equal to the magnitude of the component in the vehicle motion direction of . When the vehicle is decelerating, it is highly likely that the vehicle will stop soon, and there is a possibility that the vehicle will stop on an uphill road. Further, the component of the vehicle motion direction of gravity acting on the vehicle acts in the direction of retracting the vehicle when the vehicle is traveling uphill. Therefore, when the above predetermined condition is satisfied before the vehicle is stopped, the sum of the magnitude of the required driving force and the magnitude of the required braking force is set to be equal to or greater than the magnitude of the component of the vehicle motion direction of gravity acting on the vehicle, Retraction of the vehicle after stopping can be suppressed without being affected by the response delay of the actuator or drive actuator. In addition, if only the braking force is corrected to the increasing side, there is a risk that an excessive deceleration force will act on the vehicle. there is.

In the vehicle control apparatus according to the first aspect of the present invention, the actual speed of the vehicle and the required speed are respectively predetermined in the predetermined condition, that is, in the correction implementation condition, which is an implementation condition of the processing for correcting the required driving force and the required braking force to the increasing side, respectively. Anything lower than the speed of may be included. Further, in the vehicle control device according to the first aspect of the present invention, the predetermined condition may include that the vehicle is traveling on an uphill road. Further, in the vehicle control apparatus according to the first aspect of the present invention, in the predetermined condition, the magnitude of the component of the vehicle's motion direction of the gravity acting on the vehicle is the magnitude of the required driving force and the magnitude of the required braking force. A thing larger than the sum of may be included. According to the vehicle control apparatus according to the first aspect of the present invention, since the predetermined condition includes at least one of these conditions along with the vehicle being decelerated, it is possible to more accurately determine that the vehicle will stop in the near future.

In the vehicle control apparatus according to the first aspect of the present invention, the processor may be configured to correct the requested driving force and the requested braking force to the increasing side by the same value. According to the vehicle control device according to the first aspect of the present invention, the increase in the driving force and the increase in the braking force are canceled until the vehicle is stopped, so that it is possible to suppress a change in the deceleration of the vehicle. Further, in the vehicle control apparatus according to the first aspect of the present invention, the processor is configured to: a sum of the magnitude of the required driving force and the magnitude of the required braking force from the magnitude of a component of the motion direction of the vehicle of gravity acting on the vehicle may be configured to set a value equal to or greater than half the value obtained by subtracting may be

In the vehicle control device according to the first aspect of the present invention, when the predetermined condition is satisfied, the processor may be configured to gradually increase the required driving force and the required braking force up to the corrected required driving force and the required braking force. . According to the vehicle control device according to the first aspect of the present invention, it is possible to suppress a sudden change in the deceleration of the vehicle.

Further, in the vehicle control apparatus according to the first aspect of the present invention, the processor is configured to: when the state of the vehicle transitions from a deceleration state to an acceleration state or a normal running state after the predetermined condition is satisfied, the processor is configured to perform the correction to the increase side. It may be configured to re-correct the required driving force and the required braking force to the decreasing side, respectively. According to the vehicle control device according to the first aspect of the present invention, it is possible to suppress a decrease in fuel efficiency due to transition to the acceleration state or the normal running state while leaving the braking force. In the vehicle control device according to the first aspect of the present invention, in the vehicle control device according to the first aspect of the present invention, when the state of the vehicle transitions from a deceleration state to an acceleration state or a steady running state after the predetermined condition is satisfied, the request corrected to the increasing side The driving force and the required braking force may be gradually decreased toward the required driving force and the required braking force before correction, respectively. According to the vehicle control device according to the first aspect of the present invention, it is possible to suppress disturbances in the behavior of the vehicle due to sudden changes in driving force or braking force.

Further, in the vehicle control device according to the first aspect of the present invention, the processor receives a situation in which the predetermined condition is satisfied, corrects the required driving force and the required braking force to the increasing side, respectively, and then increases the actual speed of the vehicle. It may be configured to decrease the required driving force or increase the required braking force when a decrease in followability with respect to the requested speed is confirmed. According to the vehicle control device according to the first aspect of the present invention, it is possible to improve the speed followability lowered due to the operation error of the braking actuator or the driving actuator.

A vehicle control device according to a second aspect of the present invention is mounted on a vehicle including a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force. The vehicle control device includes a processor. The processor is configured to: based on a component of a motion direction of the vehicle of a required acceleration for the vehicle and a gravity acting on the vehicle, such that an acceleration in a motion direction of the vehicle acting on the vehicle meets the required acceleration, and set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator. The processor is configured to control the driving actuator based on the requested driving force. The processor is configured to control the braking actuator based on the required braking force. The processor is configured to determine that the sum of the magnitude of the required driving force and the magnitude of the required braking force is calculated as a value of gravity acting on the vehicle when a predetermined condition including at least the actual speed and the required speed of the vehicle are respectively lower than the predetermined speed is satisfied. and correcting the required driving force and the required braking force to the increasing side, respectively, so as to be greater than or equal to the magnitude of the component in the vehicle motion direction of . In a state where the actual speed of the vehicle and the required speed are low, respectively, the vehicle is highly likely to stop soon, and there is a possibility that the vehicle will stop on an uphill road. Therefore, when the predetermined condition (correction execution condition) is satisfied before the vehicle is stopped, the sum of the magnitude of the required driving force and the magnitude of the required braking force is equal to or greater than the magnitude of the component of the vehicle motion direction of the gravity acting on the vehicle. By doing so, the retreat of the vehicle after stopping can be suppressed without being affected by the response delay of the braking actuator or the driving actuator.

A vehicle control device according to a third aspect of the present invention is mounted on a vehicle including a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force. The vehicle control device includes a processor. The processor is configured to: based on a component of a motion direction of the vehicle of a required acceleration for the vehicle and a gravity acting on the vehicle, such that an acceleration in a motion direction of the vehicle acting on the vehicle meets the required acceleration, and set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator. The processor is configured to control the driving actuator based on the requested driving force. The processor is configured to control the braking actuator based on the required braking force. The processor is configured to determine that, when a predetermined condition including that at least the vehicle is traveling uphill is satisfied, the sum of the magnitude of the required driving force and the magnitude of the required braking force is a component of the vehicle motion direction of gravity acting on the vehicle and correcting the required driving force and the required braking force to the increasing side, respectively, so as to be greater than or equal to the magnitude of . When the vehicle is traveling on an uphill road, there is a possibility that the vehicle stops on the uphill road. Therefore, when the predetermined condition (correction execution condition) is satisfied before the vehicle is stopped, the sum of the magnitude of the required driving force and the magnitude of the required braking force is equal to or greater than the magnitude of the component of the vehicle motion direction of the gravity acting on the vehicle. By doing so, the retreat of the vehicle after stopping can be suppressed without being affected by the response delay of the braking actuator or the driving actuator.

A vehicle control device according to a fourth aspect of the present invention is mounted on a vehicle including a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force. The vehicle control device includes a processor. The processor is configured to: based on a component of a motion direction of the vehicle of a required acceleration for the vehicle and a gravity acting on the vehicle, such that an acceleration in a motion direction of the vehicle acting on the vehicle meets the required acceleration, and set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator. The processor is configured to control the driving actuator based on the requested driving force. The processor is configured to control the braking actuator based on the required braking force. The processor is configured to, when a predetermined condition including that at least a magnitude of a component of a motion direction of the vehicle of gravity acting on the vehicle is greater than a sum of the magnitude of the required driving force and the magnitude of the required braking force is satisfied, the request and correcting the required driving force and the required braking force to the increasing side, respectively, so that the sum of the magnitude of the driving force and the magnitude of the required braking force is equal to or greater than the magnitude of a component of the moving direction of the vehicle of gravity acting on the vehicle. When the magnitude of the component of the vehicle motion direction of gravity acting on the vehicle is larger than the sum of the magnitude of the required driving force and the magnitude of the required braking force, the vehicle is highly likely to stop immediately, and the vehicle may stop on an uphill road. Therefore, when the predetermined condition (correction execution condition) is satisfied before the vehicle is stopped, the sum of the magnitude of the required driving force and the magnitude of the required braking force is equal to or greater than the magnitude of the component of the vehicle motion direction of the gravity acting on the vehicle. By doing so, the retreat of the vehicle after stopping can be suppressed without being affected by the response delay of the braking actuator or the driving actuator.

According to the vehicle control apparatus according to the first to fourth aspects of the present invention, when the correction execution condition is satisfied before the vehicle is stopped, the required driving force and the required braking force are respectively corrected to the increasing side, and the magnitude of the required driving force and the required braking force are corrected. By setting the sum of the magnitudes of , greater than or equal to the magnitude of the component in the vehicle motion direction of gravity acting on the vehicle, it is possible to suppress the vehicle's retreat on an uphill road without being affected by the response delay of the braking actuator or the driving actuator.

BRIEF DESCRIPTION OF THE DRAWINGS The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like numbers indicate like elements, wherein:
1 is a diagram showing the balance of forces during acceleration in a vehicle traveling on an uphill road.
Fig. 2 is a diagram showing the balance of forces at the time of deceleration in a vehicle traveling on an uphill road.
3 is a diagram illustrating a relationship between a driving force and a braking force at which the vehicle does not start to move when the vehicle is stopped.
4 is a diagram for explaining a condition in which a vehicle stopped on an uphill road retreats.
5 is a diagram showing the balance of forces in a vehicle stopped on an uphill road.
6 is a view for explaining a condition for a vehicle traveling on an uphill road not to retreat when stopped.
FIG. 7 is a view for explaining the setting of driving force and braking force so that a vehicle traveling on an uphill road does not retreat when stopped.
8 is a control block diagram of a vehicle control device according to Embodiment 1 of the present invention.
9 is a flowchart showing a control flow of braking force/driving force control according to Embodiment 1 of the present invention.
Fig. 10 is a diagram showing a control result of braking force/driving force control in a comparative example.
11 is a diagram showing an example of a control result of braking force/driving force control according to Embodiment 1 of the present invention.
12 is a diagram showing another example of the control result of the braking force/driving force control according to the first embodiment of the present invention.
13 is a flowchart showing a control flow of braking force/driving force control according to Embodiment 2 of the present invention.
14 is a diagram showing an example of a control result of braking force/driving force control according to Embodiment 2 of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings. However, in the embodiments shown below, when referring to the number, quantity, amount, range, etc. of each element, the invention is not limited to the number, except when specifically specified or clearly specified in principle. This is not limited. In addition, the structures, steps, etc. which are demonstrated in the embodiment shown below are not necessarily essential to this invention except the case where it is specifically indicated and the case where it is clearly specified in principle.

1. Overview of braking force/driving force control

First, an outline of braking force/driving force control according to an embodiment of the present invention will be described with reference to each of the drawings in FIGS. 1 to 7 . 1 and 2 are diagrams showing the balance of forces in the vehicle 2 traveling on the uphill road 100 . Observing the balance of forces in the direction parallel to the road surface, that is, the vehicle motion direction of the vehicle 2 , the vehicle 2 traveling on the uphill road 100 has a gravitational force in the direction of motion of the vehicle 2 . The component S, the driving force F, and the braking force B act. The component of the motion direction of the vehicle 2 of gravity (hereinafter simply referred to as a 'gravity component') S is a force acting in the direction of retracting the vehicle 2, and the slope angle of the uphill road 100 is θ, the vehicle If the gravity (vehicle weight) acting on (2) is W, it is a force expressed as W×sinθ. Therefore, the larger the gradient angle θ, the larger the gravitational component S. The driving force F is a force acting in the traveling direction of the vehicle 2 , and the braking force B is a force acting in a direction opposite to the traveling direction of the vehicle.

When the vehicle 2 is traveling on the uphill road 100 when accelerating, the driving force F is greater than the resultant force of the gravity component S and the braking force B, and as shown in FIG. 1 , the vehicle 2 has an acceleration force A in the traveling direction is working On the other hand, at the time of deceleration of the vehicle 2 traveling on the uphill road 100, the driving force F is smaller than the resultant force of the gravity component S and the braking force B, and as shown in FIG. A deceleration force A is acting in the reverse direction. Assuming that the deceleration force is a negative value of the acceleration force, the following relational expression holds between the driving force F, the braking force B, the gravity component S, and the acceleration force A.

F = B + S + A… Equation 1

Next, the balance of forces when the vehicle 2 stops on the uphill road 100 will be considered. On the vehicle 2 at rest on the uphill road 100 , the gravitational component S acts in the direction of retracting the vehicle. When the driving force F is applied to the vehicle 2 in this state, if the magnitude of the driving force F exceeds the magnitude of the gravity component S, the vehicle 2 tries to advance the uphill road 100 . In order to keep the vehicle 2 in a stationary state, it is necessary to apply a braking force B greater than the excess of the driving force F with respect to the gravity component S to the vehicle 2 . In this case, the braking force B acts in the opposite direction to the driving force F. The condition for not moving the vehicle 2 while stopped is expressed by the following equation.

Ｆ≤B+S… Equation 2

On the other hand, if the magnitude of the driving force F is less than the magnitude of the gravity component S, the vehicle 2 tries to retreat the uphill road 100 . In order to keep the vehicle 2 in a stationary state, it is necessary to apply a braking force B greater than the shortfall of the driving force F with respect to the gravity component S to the vehicle 2 . In this case, the braking force B acts in the same direction as the driving force F. The condition for not retreating the vehicle 2 while stopped is expressed by the following expression.

Ｆ≥-B+S… Equation 3

When the relationship between the driving force F and the braking force B for preventing the vehicle 2 from starting to move when the vehicle 2 is stopped, expressed by Equations 2 and 3, is graphed, it is as shown in FIG. 3 . The hatched stop region in the graph is a region in which the relationship between the driving force F and the braking force B in which the vehicle 2 does not start to move when stopped is maintained. Specifically, in a region where the driving force F is greater than the gravity component S and is less than or equal to the sum of the braking force B and the gravity component S, the braking force B acts in the opposite direction to the traveling direction of the vehicle 2 , so that the vehicle 2 moves forward. is being stopped In a region where the driving force F is smaller than the gravity component S and greater than or equal to the difference between the gravity component S and the braking force B, the braking force B acts in the same direction as the traveling direction of the vehicle 2, thereby preventing the vehicle 2 from retreating. .

In the graph, a straight line is drawn showing the relationship between the driving force F and the braking force B, the gravity component S, and the acceleration force A in acceleration and deceleration, respectively. During acceleration, that is, when the acceleration force A is greater than zero, the vehicle 2 does not stop on the uphill road 100 . However, at the time of deceleration, that is, when the acceleration force A is smaller than zero, there is a possibility that the vehicle 2 will stop immediately on the uphill road 100 . When decelerating and stopping the vehicle 2, from the viewpoint of fuel efficiency, in order to suppress the consumption of the driving force F by the braking force B, the braking force B is not output and the desired deceleration force (negative acceleration force) is only adjusted by adjusting the driving force F. ) it is desirable to realize A. That is, at the time of deceleration, it is preferable to drive the vehicle 2 at the operating point indicated by the point p0 in the graph, or an operating point close thereto.

However, as shown in Fig. 4, at the operating point p0, since the gravitational component S overcomes the driving force F, the vehicle 2 starts to retreat after stopping once. At that time, even if it is attempted to increase the braking force B in a hurry, the braking force B is not immediately increased due to the response delay of the braking actuator. Similarly, there is also a response delay in the driving actuator that generates the driving force F. Therefore, in order to prevent the vehicle 2 from retreating after stopping, it is required that the balance of forces shown in Fig. 5 be realized when the vehicle 2 is stopped, even if the vehicle is being driven at the operating point p0 during deceleration. . That is, the sum of the magnitude of the braking force B and the magnitude of the driving force F is required to be equal to or greater than the magnitude of the gravity component S.

As described above, it is difficult to increase the braking force B immediately after stopping due to the response delay of the braking actuator. Then, as shown in FIG. 6 , the braking force B required after stopping may be output in advance during deceleration. When the braking force B is output during deceleration, the braking force B acts in the opposite direction to the driving force F while the vehicle 2 is traveling. However, after the vehicle 2 is stopped, the braking force B acts in the same direction as the driving force F, that is, in a direction that prevents the retreat of the vehicle 2 as indicated by the dotted line. In addition, if the braking force B is output during deceleration, there is a risk that the deceleration force A acting on the vehicle 2 becomes excessive. However, this problem can be solved by raising the driving force F by the amount by which the driving force F is canceled by the braking force B.

The process for preventing the vehicle 2 traveling on the uphill road 100 described in FIG. 6 from retreating when stopped will be described in more detail using the graph shown in FIG. 7 . In the graph, a plurality of operating points of the vehicle 2 determined by the driving force F and the braking force B are shown. Here, it is assumed that the operating point of the decelerating vehicle 2 is set to, for example, the operating point p0. As the operating point is closer to the operating point p0, a decrease in fuel efficiency during deceleration can be suppressed. However, if this is the case, since the vehicle 2 starts to retreat after stopping, when a predetermined stopping condition including that the vehicle 2 is decelerating is satisfied, the operating point is plotted against stopping of the vehicle 2 in the graph. transition into the stop zone.

In the graph, the operating points p1, p1a, p1b, and p1c are shown as examples of the selection of the operating point in the still area. Any of these operating points are permitted as long as the purpose is only that the vehicle 2 does not retract after stopping. However, from the viewpoint of fuel efficiency, it is preferable that the driving force F during a stop is smaller. That is, the operating points p1 and p1c are more preferable than the operating points p1a and p1b. On the other hand, from the viewpoint of the continuity of the deceleration, it is preferable that the deceleration force A equal to the operating point p0 is obtained. That is, the operating points p1 and p1a are more preferable than the operating points p1b and p1c. At the operating point p1b, the deceleration decreases, and at the operating point p1c, the deceleration increases, so that the occupant may feel uncomfortable. In view of the above, it is preferable to shift the operating point from the operating point p0 to the operating point p1 in general when preparing for the vehicle 2 to stop. The operating point p1 is an operating point at which a deceleration force A equal to the operating point p0 is obtained, that is, an operating point that can satisfy the relation of Equation 1 at a deceleration force A equal to the operating point p0, and with the minimum driving force F It is an operating point that can satisfy the relation of Equation 3.

2. Configuration of vehicle control unit

Next, the configuration of the vehicle control device for executing the above-described braking force/driving force control will be described. Here, as an embodiment of the present invention, for example, in the level definition of SAE (Society of Automotive Engineers), the above-described braking force/driving force control in a vehicle control device that performs driving support control at an automatic driving level of level 1 or higher is implemented. An example to be realized will be described. The driving assistance control of the level 1 or higher automatic driving level includes, for example, Autonomous Driving System (ADS) and Adaptive Cruise Control (ACC). Here, an example in which the present invention is applied to a vehicle control device equipped with an ADS will be described.

8 is a control block diagram of a vehicle control device according to an embodiment of the present invention. As will be described later, in this specification, two embodiments are disclosed with respect to braking force/driving force control. The configuration of the vehicle control device 10 shown in FIG. 8 is applicable to braking force/driving force control according to any embodiment. The vehicle control device 10 is applied to a vehicle 2 capable of independently operating a driving actuator and a braking actuator. For example, in the embodiment, as the drive actuator, a hybrid power train 3 in which an internal combustion engine and an electric motor are combined is provided. As the braking actuator, a hydraulic brake 4 is provided. In addition, the vehicle 2 is equipped with at least an acceleration sensor 5 and a wheel speed sensor as a speed sensor 6 as means for acquiring information regarding the driving state of the vehicle 2 . The information acquired by those sensors 5 and 6 is introduced into the vehicle control device 10 .

The vehicle control device 10 is an ECU (Electronic Control Unit) having at least one processor 21 and at least one memory 22 . In the memory 22, various data including maps and various programs are stored. The program stored in the memory 22 is read and executed by the processor 21 , so that various functions described below are realized in the vehicle control device 10 . In addition, the vehicle control device 10 may be a set of a plurality of ECUs.

The vehicle control device 10 includes a planner 11 . The planner 11 calculates the required acceleration and the requested speed in the case of driving the vehicle 2 along the set travel route over a predetermined period from the present to the future, and updates them at a fixed period. However, the acceleration means the acceleration in the motion direction of the vehicle 2 , that is, the ground acceleration, and the speed means the speed in the motion direction of the vehicle 2 , that is, the ground speed. The calculation of the required acceleration and the requested speed is performed for the purpose of maintaining a vehicle distance with the preceding vehicle, adjusting the vehicle speed so as not to exceed the set vehicle speed, and adjusting the vehicle speed so that the lateral acceleration does not exceed a specified value. .

The vehicle control device 10 calculates a target acceleration comprising an acceleration feed-forward term and a velocity feedback term. The required acceleration calculated by the planner 11 is used as an acceleration feed-forward term of the target acceleration (hereinafter referred to as an 'acceleration F/F term'). The speed feedback term (hereinafter referred to as 'speed F/B term') is a feedback term for matching the actual speed of the vehicle 2 obtained by the speed sensor 6 to the requested speed. The calculation of the speed F/B term is performed by the speed F/B term calculating unit 12 of the vehicle control device 10 . The speed F/B term calculating unit 12 calculates a deviation between the requested speed and the actual speed obtained from the vehicle 2 , and calculates the speed F/B term by proportional integration control for the deviation.

The vehicle control device 10 adds an acceleration feedback term for matching the actual acceleration of the vehicle 2 obtained by the speed sensor 6 to the target acceleration. The acceleration feedback term (hereinafter, referred to as an 'acceleration F/B term') is calculated by the acceleration F/B term calculating unit 13 of the vehicle control device 10 . The acceleration F/B term calculating unit 13 corrects the target acceleration by the response delay amount of the vehicle 2 to the braking operation or the driving operation, and calculates the deviation between the corrected target acceleration and the actual ground acceleration obtained from the vehicle 2 . It is calculated, and the acceleration F/B term is calculated by proportional integral control with respect to the deviation.

The vehicle control device 10 calculates the required acceleration force based on the corrected target acceleration obtained by adding the acceleration F/B term to the target acceleration. Specifically, first, the required acceleration force is calculated by multiplying the corrected target acceleration by the vehicle weight of the vehicle 2 and converting the corrected target acceleration into the acceleration force.

Next, the vehicle control device 10 calculates an acceleration force correction term for various corrections such as road surface gradient correction, air resistance correction, and rolling resistance correction. Calculation of the acceleration force correction term is performed by the acceleration force correction term calculating unit 14 . The required braking force is calculated by adding the acceleration force correction term to the requested acceleration force converted from the corrected target acceleration. In addition, among these correction terms, the road surface gradient correction term is a component of the motion direction of the vehicle 2 of gravity acting on the vehicle 2 , and corresponds to the gravity component S shown in FIG. 1 on an uphill road. The estimated value of the road surface direction of the gravitational acceleration acting on the vehicle 2 can be calculated from, for example, the difference between the acceleration obtained by the acceleration sensor 5 and the differential value of the vehicle speed obtained by the wheel speed sensor serving as the speed sensor 6. . In addition, by applying the current position of the vehicle 2 obtained by GPS to the map having the road surface gradient information, it is also possible to obtain the road surface gradient information at the current position of the vehicle 2 .

The required braking force corresponds to the value obtained by adding the gravitational component S to the acceleration force A shown in Fig. 1 on an uphill road. The vehicle control device 10 distributes the required braking force into a braking force and a driving force in the braking force/driving force distribution unit 15 . This distribution is performed in accordance with a predetermined distribution rule, giving priority to, for example, the best fuel economy. Taking the time of deceleration as an example, the required braking force is distributed only to the driving force within the range in which the required braking force can be realized by reducing the driving force. Then, after the driving force is reduced to the minimum driving force that the power train 3 can output, the remainder obtained by subtracting the minimum driving force from the required braking force is distributed as the braking force. For example, when decelerating on an uphill road, the braking force and driving force corresponding to the operating point p0 shown in the graph of FIG. 3 are calculated.

The vehicle control device 10 corrects the braking force and driving force distributed from the requested braking force in the braking force/driving force correction unit 16 . To the power train control unit 17 that operates the power train 3 , the corrected driving force is applied as the required driving force. To the brake control unit 18 that operates the brake 4, the corrected braking force is applied as the required braking force. The power train control unit 17 operates the power train 3 with an operation amount for realizing the required driving force. The amount of operation of the power train 3 is, for example, a fuel injection amount when traveling by an internal combustion engine, and a current when traveling by an electric motor. The brake control unit 18 operates the brake 4 with an operation amount for realizing the required braking force. The amount of operation of the brake 4 is specifically the brake master pressure or the brake stroke amount.

The braking force/driving force correction unit 16 corrects the braking force and the driving force according to the transition between the running state and the running state of the vehicle 2 . The traveling state includes stopping, traveling, and transitioning from traveling to stop. The braking force/driving force correction unit 16 determines the transition between these traveling states as follows.

<Transitioning from driving to stopping>

The transition from running to stopping transition is determined by the requirement that the required acceleration calculated by the planner 11 is a negative value, that is, that deceleration is being requested (requirement 1), and the required speed calculated by the planner 11 and It is a condition that all of the requirements (requirement 2) that the actual speeds obtained by the speed sensor 6 are each less than a predetermined minute speed (for example, 5 km/h) are satisfied. However, the threshold values of the requested speed and the actual speed may be variable according to the requested acceleration so that the threshold becomes larger as the deceleration requested is larger.

<From stopping transition to stopping>

The transition from stopping transition to stopping is a condition that the requested speed calculated by the planner 11 and the actual speed obtained by the speed sensor 6 become zero, respectively.

<From stopping or transitioning from stopping to driving>

For the transition from stopping to traveling and transition from stopping transition to traveling, the condition is that the required acceleration calculated by the planner 11 is a positive value.

The braking force/driving force correcting unit 16, for example, when the driving state of the vehicle 2 transitions from driving on an uphill road to transitioning to a stop, the braking force and driving force corresponding to the operating point p1 shown in the graph of FIG. 7 . The required driving force and the required braking force are respectively corrected so that this can be obtained. However, the correction by the braking force/driving force correction unit 16 is not performed in all driving states. For example, during simple driving, correction is not performed, and the braking force and driving force calculated by the braking force/driving force distribution unit 15 are directly transferred to the power train control unit 17 and the brake control unit 18 as the required braking force and the required driving force. is granted

The braking force/driving force correction unit 16 constitutes a “setting unit” together with the braking force/driving force distribution unit 15 . In addition, the power train control unit 17 and the brake control unit 18 constitute a “control unit”. In the following chapters, the details of the braking force/driving force control by the vehicle control device 10, including the correction of the braking force and driving force by the braking force/driving force correction unit 16, are described using a flowchart and a graph of the control result. Explain.

3. Details of the braking force/driving force control according to the first embodiment

9 is a flowchart showing a control flow of braking force/driving force control by the vehicle control device 10 according to the first embodiment of the present invention. The vehicle control device 10 repeatedly executes the processing shown in this flowchart. Hereinafter, a control flow of braking force/driving force control according to the first embodiment will be described with reference to a flowchart.

First, in step S100, it is determined whether the vehicle 2 is stopped. This determination is made, for example, based on the actual speed obtained by the speed sensor 6 and the requested acceleration set by the planner 11 . If the stall speed is zero and the required acceleration is zero, it may be determined that the vehicle 2 is stopped.

If the vehicle 2 is stopped, the determination of step S200 is performed. In step S200 , it is determined whether the vehicle 2 is stopped only by the braking force of the brake 4 . This determination can be made, for example, based on a comparison between the magnitude of the component of the motion direction of the vehicle 2 of gravity acting on the vehicle 2 and the magnitude of the braking force generated by the brake 4 . The magnitude of the component of the motion direction of the vehicle 2 of gravity acting on the vehicle 2 can be obtained from the acceleration sensor 5 . The magnitude of the braking force generated by the brake 4 can be calculated from the amount of operation of the brake 4 .

When the vehicle 2 is stopped with only the braking force of the brake 4 , the process of step S300 is performed. In step S300, the required driving force for the power train 3 is gradually decreased in a predetermined gradual gradient up to the minimum driving force that the power train 3 can generate. As an example of the value of a gradual gradient, -20000N/s is mentioned. If the driving force is already the minimum driving force of the power train 3, maintaining that state is done.

When the vehicle 2 is not stopped only by the braking force of the brake 4 , the process of step S400 is performed. In step S400, the required braking force for the brake 4 is gradually increased with a predetermined gradual gradient up to the maximum braking force calculated by the following equation (4).

Maximum Braking Force = (|Estimated Road Gradient|*(1 + Gradient Gain Error) + Road Gradient Offset Error)*Maximum Vehicle Weight… Equation 4

In Equation 4, the estimated road gradient is an estimated value of the road surface direction of the gravitational acceleration, and can be calculated as, for example, the difference between the acceleration obtained by the acceleration sensor 5 and the differential value of the vehicle speed obtained by the speed sensor 6 . When the vehicle 2 is traveling on an uphill road, the estimated road slope becomes a positive value, and when the vehicle 2 is traveling on a downhill road, the estimated road slope becomes a negative value. The road surface gradient gain error is a gain error of the estimated road surface gradient value, and an example of the setting is 0.05. The road surface gradient offset error is an offset error of the estimated road surface gradient value, and an example of the setting is 0.7 m/s ² . The maximum vehicle weight is the maximum weight of the vehicle 2 in consideration of the error, and an example of the setting is 1.2 times the standard vehicle weight. According to Equation 4, even when there is an error in the estimated road surface gradient value or the vehicle weight, the maximum braking force is calculated based on the error so that the vehicle 2 can be prevented from retreating when it is stopped. Moreover, 5400 N/s is mentioned as an example of the value of an incremental gradient.

When it is determined in step S100 that the vehicle 2 is not stopped, the processing after step S500 is performed. First, in step S500, the required braking force is calculated. Next, in step S600, the required braking force is distributed into the braking force and the driving force according to a predetermined distribution rule. Note that the calculation method of the required braking force and the method of distributing the required braking force are the same as those described in the description of the configuration of the vehicle control device 10 .

Next, in step S700, it is determined whether the vehicle 2 is in the middle of a stop transition. Whether or not the vehicle 2 is in the stop transition is judged by the success or failure of the above-described transition condition from traveling to stopping transition. To reiterate, when the requested acceleration calculated by the planner 11 is a negative value and the requested speed and the actual speed are respectively less than a predetermined minute speed, it is determined that the vehicle 2 is in the process of stopping.

When the vehicle 2 is moving to a stop, the determination of step S800 is continuously performed. In step S800 , it is determined whether or not a correction for raising the required driving force and required braking force for preventing the vehicle 2 from retreating after stopping is necessary. 7 , when the operating point of the vehicle 2 is located in a region where the driving force F is lower than the difference between the gravity component S and the braking force B, the vehicle 2 starts to retreat after stopping. In this case, it is necessary to raise the required driving force and required braking force for each value calculated in step S600 so that the operating point of the vehicle 2 falls within the stop region in the graph.

In detail, in step S800, first, the required pulling-up amounts of the required driving force and the required braking force are calculated by the following equation (5). Referring to the graph of FIG. 7 , the required amount of lift is the amount of lift required to put the operating point of the vehicle 2 in the stop region after taking into account the error of the road surface gradient or the error of the vehicle weight. The required pulling-up amount of the required driving force and the required pulling-up amount of the required braking force are set to the same value. This is to suppress a change in the deceleration before and after the pulling so that the driving force increase and the braking force increase mutually cancel each other.

Required increase amount = ((Estimated road slope + | Estimated road slope | * Road slope gain error + road slope offset error) * Maximum vehicle weight-required driving force before correction-required braking force before correction)/2… Equation 5

In step S800, it is then determined whether or not the required lifting amount calculated in Expression 5 is greater than zero. Then, if the required pulling amount is greater than zero, it is determined that the pulling correction of the required driving force and the required braking force is necessary. If the required pulling amount is zero or less, it means that the current operating point of the vehicle 2 is already within the stopping area. Accordingly, in that case, there is no fear that the vehicle 2 will retreat, and further correction of the increase in the required driving force and the required braking force is not required.

In order for the required increase amount to be greater than zero, the estimated road surface gradient needs to be a positive value. That is, that the vehicle 2 is traveling on an uphill road is one of the necessary conditions for performing the correction of the increase in the required driving force and the required braking force. In addition, in Equation 5, "road surface gradient estimated value + | road surface gradient estimated value | * road gradient gain error + road surface gradient offset error" is the value of the vehicle 2 of gravity acting on the vehicle 2 in a state in which the error is taken into account. It represents the magnitude of the component in the direction of motion. Therefore, in Equation 5, the magnitude of the component of the motion direction of the vehicle 2 of the gravity acting on the vehicle is greater than the sum of the magnitude of the required driving force and the magnitude of the required braking force. This means that it is a necessary and sufficient condition for

When it is determined in step S800 that the pulling correction of the requested driving force and the required braking force is necessary, the processing of step S900 is performed. In step S900, the required braking force is not increased rapidly to the required pulling amount, but is gradually increased at a predetermined calculation cycle as shown in the following equations (6) and (7). Equation 6 means that the smaller value among the value obtained by adding the value obtained by multiplying the braking force increase jerk by the calculation period to the previous value of the braking force increase amount and the required increase amount is selected as the braking force increase amount. Further, in Equation 6, the braking force raising jerk defines an increase rate for each calculation period of the required braking force. The previous value of the braking force increase in Expression 6 is reset to zero at the timing at which the determination of whether or not the pulling correction is necessary in step S800 is changed from necessary to unnecessary.

Braking force increase amount = min((last value of braking force increase amount + braking force increase jerk * calculation period), required increase amount)… Equation 6

The required braking force after correction = the required braking force before correction + the amount of braking force increase… Equation 7

In addition, in step S900, the requested driving force is not increased rapidly to the required pulling amount, but is gradually increased at a predetermined calculation period as shown in the following equations (8) and (9). The meaning of Equation 8 is the same as the meaning of Equation 6. Further, in Equation 8, the driving force raising jerk defines an increase rate for each calculation period of the required driving force. The previous value of the driving force increase amount in Equation 8 is reset to zero at the timing at which the determination of whether or not the pulling correction is necessary in step S800 is changed from necessary to unnecessary.

Driving force increase = min((Last value of driving force increase + driving force increase jerk * calculation cycle), required increase amount)… Equation 8

Demanded driving force after correction = Demanded driving force before correction + amount of driving force increase… Equation 9

In Expressions 6 and 8, the braking force pulling jerk and the driving force pulling jerk are set in consideration of the influence on the behavior of the vehicle 2 . An example of the setting is 2.7 m/s ³ . In addition, the calculation period is 10 ms, for example. However, the respective values of the braking force increase amount and the driving force increase amount may be processed by a response compensation filter in consideration of the responsiveness of the brake 4 or power train 3 . Further, the time constant of the response compensation filter may be changed according to the running state of the vehicle 2 .

When it is determined in step S800 that the correction of pulling up of the required driving force and the required braking force is unnecessary, the processing of step S1000 is performed. In step S1000, the required braking force before correction is applied from the braking force/driving force correction unit 16 to the brake control unit 18, and the brake 4 is controlled according to the required braking force before correction. Further, the required driving force before correction is given from the braking force/driving force correcting unit 16 to the power train control unit 17, and the power train 3 is controlled in accordance with the required driving force before correction.

Next, as a result of the determination in step S700, a case will be described in which the vehicle 2 is not transitioning to a stop. The case in which the vehicle 2 is not stopped and not in the transition to a stop includes a case in which the vehicle 2 is running normally and a case in which the vehicle 2 is transitioning from stopping transition to running. Also, this includes the case where the vehicle 2, which was in the transition to a stop, starts to accelerate again.

When the vehicle 2 is not in the transition to a stop, the determination of step S1100 is successively performed. In step S1100, it is determined whether or not the pulling correction of the required driving force and the required braking force has been performed. When the pulling correction of the requested driving force and the required braking force is performed in step S900 and the pulling amount has not yet returned to zero in step S1200, which will be described later, it is determined that the pulling correction is in progress.

When it is determined in step S1100 that the pulling-up correction of the requested driving force and the required braking force is being executed, the processing of step S1200 is performed. In step S1200, pulling is canceled to restore the requested braking force to its original value. By canceling the raise, it is possible to suppress a decrease in fuel efficiency due to the transition to the acceleration state or the normal running state while raising the braking force. However, the braking force increase amount is not drastically reduced to zero, but is gradually decreased in a predetermined calculation cycle as shown in Expressions 10 and 11 below. Equation 10 means that the value obtained by subtracting the value obtained by multiplying the braking force reduction jerk by the calculation period from the previous value of the braking force increase amount and zero, whichever is greater, is selected as the braking force increase amount. Also, in Equation 10, the braking force reduction jerk defines a reduction rate for each calculation period of the required braking force.

Braking force increase = max((last value of braking force increase - braking force reduction jerk * operation period), 0)… Equation 10

The required braking force after correction = the required braking force before correction + the amount of braking force increase… Equation 11

In addition, in step S1200, the required driving force is not reduced sharply to zero, but is gradually decreased at a predetermined calculation cycle as shown in Expressions 12 and 13 below. The meaning of Equation 12 is the same as the meaning of Equation 10. Further, in Equation 12, the driving force reduction jerk defines a reduction rate for each calculation period of the required driving force.

Driving force increase = max((Last value of driving force increase - driving force reduction jerk * operation period), 0)… Equation 12

Demanded driving force after correction = Demanded driving force before correction + amount of driving force increase… Equation 13

In Expressions 10 and 12, the braking force reduction jerk and the driving force reduction jerk are set in consideration of the influence on the behavior of the vehicle 2 . An example of the setting is 2.7 m/s ³ . In addition, the calculation period is 10 ms, for example. However, similarly to the case of step S900, the respective values of the braking force increase amount and the driving force increase amount may be processed by a response compensation filter in consideration of the responsiveness of the brake 4 or power train 3 .

When it is determined in step S1100 that the pulling-up correction of the requested driving force and the required braking force is not being executed, the processing of step S1300 is performed. In step S1300, the required braking force calculated in step S600 is applied from the braking force/driving force correction unit 16 to the brake control unit 18, and the brake 4 is controlled according to the required braking force. Further, the required driving force calculated in step S600 is applied from the braking force/driving force correcting unit 16 to the power train control unit 17, and the power train 3 is controlled in accordance with the required driving force.

4. Control result of braking force/driving force control according to Embodiment 1

Next, the effect of the braking force/driving force control according to the first embodiment will be described based on the actual control result. First, as a comparative example of the braking force/driving force control according to the first embodiment, the control result of the braking force/driving force control in which the function for suppressing the retreat of the vehicle 2 is not implemented will be described, and then the braking force according to the first embodiment / Consider two examples of the control result of the driving force control.

Fig. 10 is a diagram showing a control result of braking force/driving force control in a comparative example. The upper part of FIG. 10 is a graph of velocity, and the lower part is a graph of acceleration. On the graph of the speed, a line indicating the change with time between the requested speed and the actual speed is drawn. In the graph of the acceleration, a line representing the change with time of the required ground G, the actual ground G, the required drive G, the required brake G, the gradient G, the stop G, and the total of the required drive G and the required brake G is drawn. In addition, the required ground G means the required acceleration, the actual ground G means the actual acceleration, the required drive G means the required driving force divided by the vehicle weight, and the required braking G is the required braking force divided by the vehicle weight. , the gradient G denotes the component in the downhill direction of the gravitational acceleration, and the stop G denotes the maximum braking force calculated in Equation 4 divided by the vehicle weight.

FIG. 10 graphically shows a control result when the running state of the vehicle 2 transitions from traveling to stopping transition, and transitioning from stopping transition to stopping. ^{Here, as a prerequisite, it is assumed that the vehicle 2} is traveling on an uphill road where the gradient G is 2 m/s 2 , and the minimum driving force of the power train 3 is zero N. The same prerequisites are also used in the control result of the braking force/driving force control according to the first embodiment, which will be described later.

In the control result of the comparative example, the actual speed is controlled in accordance with the requested speed, and the actual ground G is controlled in accordance with the requested ground G. In addition, both the requested speed and the actual speed are set to zero at one point, and the vehicle 2 in the meantime is being stopped. In the comparative example, the control for making the requested ground G follow the actual ground G is performed only by the requested drive G, and even after the transition from the stop transition to the stop transition during the stop transition, the brake demand G is maintained at zero. However, in the comparative example, the required drive G after the vehicle 2 is stopped is insufficient compared to the gradient G. After the vehicle 2 has stopped once, the fact that the required speed is zero but the actual speed is less than zero indicates that the vehicle 2 is retreating. That is, when the function of suppressing the vehicle 2 from moving backward is not mounted, the vehicle 2 may retreat on the uphill road as in the comparative example.

11 shows an example of the control result of the braking force/driving force control according to the first embodiment. The uppermost end of Fig. 11 is a graph of speed, the second stage is a graph showing the running state, the third stage is a graph showing the pulling state of the required braking G and the required driving G, and the lowermost stage is a graph of acceleration. As in the comparative example, FIG. 11 graphically shows the control result when the driving state of the vehicle 2 transitions from traveling to stopping transition, and also transitioning from stopping transition to stopping.

The difference between the control result shown in Fig. 11 and the control result of the comparative example lies in the change in the required braking G and the required driving G after the vehicle 2 is in the stop transition. If the requested speed and the actual speed become less than the predetermined speed when the requested ground G is a negative value, it is determined that the running state of the vehicle 2 has transitioned from running to stopping transition. When the flag during the stop transition is raised, it is determined whether the pull-up correction of the demand braking G and the demand driving G is necessary. In the control result shown in Fig. 11, since the gradient G is larger than the sum of the demand braking G and the demand driving G, it is determined that the pull-up correction of the demand braking G and the driving demand G is necessary. The above determination corresponds to steps S700 and S800 of the control flow shown in Fig. 9 .

When the flag of the lift correction is set, the pull correction of the demand braking G and the demand driving G is started. By raising correction, the demand braking G and the demand driving G gradually increase at a constant increase rate, and when the sum of the demand braking G and the demand driving G becomes the stop G or more, the demand braking G and the demand driving G temporarily hold their values. do. This processing corresponds to step S900 of the control flow shown in FIG. When the vehicle 2 is stopped in this state, the sum of the required braking G and the required driving G is greater than the gradient G, so that the vehicle 2 is prevented from retreating.

When the requested speed and the actual speed respectively become zero, it is determined that the running state of the vehicle 2 has transitioned from the stop transition to the stop. This determination corresponds to step S100 of the control flow shown in FIG. When the stop flag is raised, the brake demand G is incremented until the brake demand G reaches a stop G. This processing corresponds to steps S200 and S400 of the control flow shown in FIG. In addition, in the control result shown in FIG. 11, when the running state of the vehicle 2 transitions from stopping transition to stopping, the required drive G increases rapidly in a step shape. This corresponds to the change of the requested land G from a negative value to zero in a step shape with the completion of the stop of the vehicle 2 . While the demand brake G is increasing, the demand drive G is held at a constant value.

After the brake demand G reaches the stop G, it is determined that the vehicle 2 is stopped with only the braking force, and the brake demand G is maintained at the stop G. On the other hand, the demand drive G drops to zero. This processing corresponds to steps S200 and S300 of the control flow shown in FIG. However, although the demand drive G drops sharply to zero here, the demand drive G may be gradually decreased as described in step S300. According to the control result shown in FIG. 11 , even after the traveling state of the vehicle 2 transitions from stopping transition to stopping, the actual speed is not smaller than zero. From this point, it can be seen that, according to the braking force/driving force control according to the first embodiment, retreat of the vehicle 2 can be prevented.

Next, another example of the control result of the braking force/driving force control according to the first embodiment will be described with reference to FIG. 12 . The uppermost stage of FIG. 12 is a graph of speed, the second stage is a graph showing the running state, the third stage is a graph showing the pulling state of the demand braking G and the demand driving G, and the lowest stage is a graph of acceleration. FIG. 12 is a graph showing the control result when the driving state of the vehicle 2 transitions from traveling to stopping transition, and then transitions from stopping transition to traveling again without stopping as it is.

In the control result shown in Fig. 12, the requested land G is changed from a negative value to a positive value during the stop transition. Thereby, it is determined that the traveling state of the vehicle 2 has transitioned from stopping transition to traveling, and a flag during stop transition is raised. This determination corresponds to step S700 of the control flow shown in FIG. When the stop flag is lowered, the demand braking G and the demand driving G raised during the stop transition are gradually decreased at a constant rate of decrease. This processing corresponds to steps S1100 and S1200 of the control flow shown in FIG. In addition, in the control result shown in FIG. 12 , when the running state of the vehicle 2 transitions from stopping transition to running, the required drive G increases rapidly in a step shape. This corresponds to a change in the required ground G from a negative value to a positive value in a step shape accompanying re-acceleration of the vehicle 2 .

Eventually, when the pulling is canceled and the required braking G becomes zero, a flag for raising correction is lowered. After the raise correction flag is lowered, the required braking G is maintained at zero and the required driving G is increased according to the increase in the required ground G. This processing corresponds to steps S1100 and S1300 of the control flow shown in FIG. According to the control result shown in Fig. 12, the actual speed follows the change in the requested speed from the stop transition to the running. Accordingly, it can be seen that according to the braking force/driving force control according to the first embodiment, it is possible to smoothly transition from the deceleration state to the acceleration state. In addition, although the control result shown in FIG. 12 shows the case where the vehicle 2 transitions from the deceleration state to the acceleration state, according to the braking force/driving force control according to Embodiment 1, the vehicle 2 is normalized from the deceleration state. Smooth transition can be realized even when transitioning to the running state.

5. Details of the braking force/driving force control according to the second embodiment

Next, the braking force/driving force control according to the second embodiment of the present invention will be described. 13 is a flowchart showing a control flow of braking force/driving force control by the vehicle control device 10 according to the second embodiment. The vehicle control device 10 repeatedly executes the processing shown in this flowchart. Hereinafter, the control flow of the braking force/driving force control according to the second embodiment will be described with reference to a flowchart. However, in the control flow shown in FIG. 13, the description and the judgment and processing of the same content as the control flow of Embodiment 1 will be abbreviate|omitted or simplified.

In the control flow shown in Fig. 13, when it is determined in step S800 that the pulling correction of the required driving force and the required braking force is necessary, the determination is made in step S810, and the processing of step S820 or step S900 is performed according to the determination result. There is a characteristic. The increase correction of the required driving force and the required braking force is performed so that the increment of the braking force is offset by the increment of the driving force. However, since there is an error in the operation of the power train 3 and the brake 4, it can be assumed that the braking force is actually insufficient, and the followability of the actual speed to the required speed is lowered. Step S810 is a step for confirming whether or not the followability of the actual speed to the requested speed is lowered.

In step S810, if the stall speed is increased during the vehicle 2 stop transition, it is determined that the followability of the stall speed to the requested speed has decreased. Also, when the state where the requested speed is zero during the stop transition continues for a certain period of time (for example, 1 second), that is, even when the actual speed does not become zero even after a certain period of time has elapsed after the requested speed becomes zero, the speed followability is not judged to be degraded.

When the decrease in speed followability is not confirmed in step S810, the process of step S900 is performed similarly to the case of the first embodiment. On the other hand, when a decrease in speed followability is confirmed, the process of step S820 is performed. In step S820, the respective pulling amounts of the required braking force and the required driving force are adjusted according to the following Expressions 14 and 15.

Braking force increase amount = min((last value of braking force increase amount + braking force increase jerk * calculation period), required increase amount)… Equation 14

Driving force increase = max((Last value of driving force increase - driving force reduction jerk * operation period), 0)… Equation 15

Equation 14 is equivalent to Equation 6 described above and Equation 15 is equivalent to Equation 12 described above. That is, when the speed followability is lowered, the required driving force is gradually decreased while increasing the required braking force. By performing this process, the deceleration force acting on the vehicle 2 becomes large, and the reduction of the stall speed is promoted. In addition, in Expression 15, the value of the driving force reduction jerk may be zero. Even if the driving force increase amount is maintained while the braking force increase amount is increased, the actual speed is decreased and the speed followability is improved.

6. Control result of braking force/driving force control according to Embodiment 2

Next, an example of the control result of the braking force/driving force control according to the second embodiment will be described with reference to FIG. 14 . The uppermost end of FIG. 14 is a graph of speed, the second stage is a graph showing the running state, the third stage is a graph showing the pulling state of the required braking G and the required driving G, and the lowermost stage is a graph of the acceleration. Fig. 14 is a graph showing the control result in the case where the speed followability decreases after the traveling state of the vehicle 2 transitions from traveling to stopping transition.

According to the control result shown in Fig. 14, the stall speed is increasing during the stop transition. When an increase in the actual speed is determined during the stop transition, the required drive G is gradually decreased at a constant rate of decrease while gradually increasing the required braking G as it is. This processing corresponds to steps S810 and S820 of the control flow shown in Fig. 13 . According to the control result shown in Fig. 14, as a result of gradually decreasing the required drive G, the actual speed once deviating from the requested speed is again following the requested speed. From this point, it can be seen that according to the braking force/driving force control according to the second embodiment, the followability of the stall speed to the required speed can be ensured while preventing the vehicle 2 from retreating.

In the control result shown in Fig. 14, at the timing when the pulling amount of the requested drive G becomes zero, the gradation of the requested drive G is stopped, and the requested drive G is maintained as it is. Then, at the timing when the required brake G reaches the stop G, the required drive G is off to zero. However, after the decrease in speed followability is eliminated, the demand drive G may be gradually increased again along with the demand braking G in accordance with the processing of step S900.

7. Other embodiments

As the correction execution condition, which is an execution condition of the processing for correcting the required driving force and the required braking force to the increasing side, respectively, the vehicle may only be decelerating. That is, on the condition that the vehicle is decelerating, the required driving force and the required braking force may be respectively corrected to the increasing side. This is because, when the vehicle is decelerating, it is highly likely that the vehicle will stop soon, and there is a possibility that the vehicle will stop on an uphill road. By setting the correction execution condition that the vehicle is decelerating, the retreat of the vehicle after stopping can be suppressed without being affected by the response delay of the braking actuator or the driving actuator. However, it goes without saying that it may be combined with other conditions to be described later as the conditions for performing the correction.

In addition, as the correction execution condition, the actual speed of the vehicle and the requested speed may only be lower than the predetermined speed, respectively. That is, the required driving force and the required braking force may be corrected to the increasing side, respectively, on the condition that the required speed of the vehicle is lowered and the actual speed is also lowered to follow it. This is because, in a state where both the vehicle's stall speed and the required speed are low, the vehicle is likely to stop soon, and there is a possibility that the vehicle will stop on an uphill road. By making the correction execution condition that the actual speed of the vehicle and the requested speed are lower than the predetermined speed, respectively, the retreat of the vehicle after stopping can be suppressed without being affected by the response delay of the braking actuator or the driving actuator. However, it goes without saying that it may be combined with other conditions to be described later as the conditions for performing the correction.

In addition, as the above-mentioned correction implementation condition, only the vehicle may be traveling on an uphill road. That is, on the condition that the vehicle is traveling on an uphill road, the required driving force and the required braking force may be respectively corrected to the increasing side. This is because, when the vehicle is traveling on an uphill road, there is a possibility that the vehicle will stop on the uphill road. By setting the correction execution condition to the fact that the vehicle is traveling uphill, the retreat of the vehicle after stopping can be suppressed without being affected by the response delay of the braking actuator or the driving actuator. However, it goes without saying that it may be combined with other conditions to be described later as the conditions for performing the correction.

In addition, as the above-mentioned correction implementation condition, the magnitude of the component of the vehicle motion direction of gravity acting on the vehicle may only be greater than the sum of the magnitude of the required driving force and the magnitude of the required braking force. When the magnitude of the component of the vehicle motion direction of gravity acting on the vehicle is larger than the sum of the magnitude of the required driving force and the magnitude of the required braking force, the vehicle is highly likely to stop immediately, and there is a possibility that the vehicle may stop on an uphill road. am. In addition, when the error of the road surface gradient and the error of the vehicle weight are taken into consideration, it is good also considering that the right side of Equation 5 is greater than zero as the above-mentioned correction implementation condition.

Claims (13)

A vehicle control device mounted on a vehicle comprising a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force, the vehicle control device comprising:
The vehicle control device includes a processor (21),
The processor 21 is configured to be configured such that, based on the component of the required acceleration for the vehicle and the component of the moving direction of the vehicle of gravity acting on the vehicle, the acceleration in the moving direction of the vehicle acting on the vehicle satisfies the required acceleration. configured to set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator,
The processor 21 is configured to control the driving actuator based on the required driving force,
The processor 21 is configured to control the braking actuator based on the required braking force,
The processor 21 is configured to determine, when a predetermined condition including at least that the vehicle is decelerating is satisfied, the sum of the magnitude of the required driving force and the magnitude of the required braking force is the direction of movement of the vehicle by gravity acting on the vehicle. and correcting the required driving force and the required braking force simultaneously to the increasing side, respectively, so as to be equal to or greater than the magnitude of the component of . According to claim 1,
and the predetermined condition includes that the actual speed and the requested speed of the vehicle are respectively lower than the predetermined speed. 3. The method of claim 1 or 2,
The predetermined condition includes that the vehicle is traveling on an uphill road. 3. The method of claim 1 or 2,
and the predetermined condition includes that the magnitude of the component of the vehicle motion direction of the gravity acting on the vehicle is greater than the sum of the magnitude of the required driving force and the magnitude of the required braking force. 3. The method of claim 1 or 2,
and the processor (21) is configured to correct the required driving force and the required braking force to the increasing side by the same value. 6. The method of claim 5,
The processor 21 is configured to calculate a value equal to or greater than half a value obtained by subtracting the sum of the magnitude of the required driving force and the magnitude of the required braking force from the magnitude of the component of the vehicle motion direction of the gravity acting on the vehicle, and set as a pulling amount for each of the requested driving force and the required braking force, and configured to correct the requested driving force and the required braking force to the increasing side by the pulling amount, respectively. 3. The method of claim 1 or 2,
and the processor (21) is configured to gradually increase the required driving force and the required braking force up to the required driving force and the required braking force after correction, when the predetermined condition is satisfied. 3. The method of claim 1 or 2,
The processor 21 is configured to, when the state of the vehicle transitions from a deceleration state to an acceleration state or a normal driving state after the predetermined condition is satisfied, re-correct the required driving force and the required braking force corrected to the increasing side to the decreasing side, respectively. A vehicle control device configured to 9. The method of claim 8,
The processor (21) is configured to, when the state of the vehicle transitions from a deceleration state to an acceleration state or a normal running state after the predetermined condition is satisfied, the requested driving force and the required braking force corrected to the increasing side, respectively, as the request before correction, respectively. and the vehicle control device is configured to gradually decrease toward the driving force and the required braking force. 3. The method of claim 1 or 2,
The processor 21 is configured to receive a situation in which the predetermined condition is satisfied, correct the required driving force and the required braking force to the increasing side, respectively, and then, when it is confirmed that the trackability of the vehicle's stall speed with respect to the required speed is lowered, the and a vehicle control device configured to decrease the required driving force or increase the required braking force. A vehicle control device mounted on a vehicle comprising a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force, the vehicle control device comprising:
The vehicle control device includes a processor (21),
The processor 21 is configured to be configured such that, based on the component of the required acceleration for the vehicle and the component of the moving direction of the vehicle of gravity acting on the vehicle, the acceleration in the moving direction of the vehicle acting on the vehicle satisfies the required acceleration. configured to set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator,
The processor 21 is configured to control the driving actuator based on the required driving force,
The processor 21 is configured to control the braking actuator based on the required braking force,
The processor 21 is configured to calculate the sum of the magnitude of the required driving force and the magnitude of the required braking force to the vehicle when a predetermined condition including at least the actual speed and the required speed of the vehicle are respectively lower than the predetermined speed is satisfied. and correcting the required driving force and the required braking force simultaneously to the increasing side, respectively, so as to be equal to or greater than a magnitude of a component of the moving direction of the vehicle of the applied gravity. A vehicle control device mounted on a vehicle comprising a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force, the vehicle control device comprising:
The vehicle control device includes a processor (21),
The processor 21 is configured to be configured such that, based on the component of the required acceleration for the vehicle and the component of the moving direction of the vehicle of gravity acting on the vehicle, the acceleration in the moving direction of the vehicle acting on the vehicle satisfies the required acceleration. configured to set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator,
The processor 21 is configured to control the driving actuator based on the required driving force,
The processor 21 is configured to control the braking actuator based on the required braking force,
The processor 21 is configured to calculate that the sum of the magnitude of the required driving force and the magnitude of the required braking force is the amount of gravity acting on the vehicle when at least a predetermined condition including that the vehicle is traveling uphill is satisfied. and correcting the required driving force and the required braking force simultaneously to the increasing side, respectively, so as to be equal to or greater than a magnitude of a component in a motion direction of . A vehicle control device mounted on a vehicle comprising a drive actuator configured to apply a driving force and a braking actuator configured to apply a braking force, the vehicle control device comprising:
The vehicle control device includes a processor (21),
The processor 21 is configured to be configured such that, based on the component of the required acceleration for the vehicle and the component of the moving direction of the vehicle of gravity acting on the vehicle, the acceleration in the moving direction of the vehicle acting on the vehicle satisfies the required acceleration. configured to set a required driving force to be requested from the driving actuator and a required braking force to be requested from the braking actuator,
The processor 21 is configured to control the driving actuator based on the required driving force,
The processor 21 is configured to control the braking actuator based on the required braking force,
When a predetermined condition including that at least a magnitude of a component of a motion direction of the vehicle of gravity acting on the vehicle is greater than the sum of the magnitude of the required driving force and the magnitude of the required braking force is satisfied , so that the required driving force and the required braking force are simultaneously corrected to the increasing side so that the sum of the magnitude of the required driving force and the magnitude of the required braking force is equal to or greater than the magnitude of a component of the vehicle's motion direction of gravity acting on the vehicle. A vehicle control device comprising:

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